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Asejeje FO, Abiola MA, Adeyemo OA, Ogunro OB, Ajayi AM. Exogenous monosodium glutamate exacerbates lipopolysaccharide-induced neurobehavioral deficits, oxidative damage, neuroinflammation, and cholinergic dysfunction in rat brain. Neurosci Lett 2024; 825:137710. [PMID: 38432355 DOI: 10.1016/j.neulet.2024.137710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/17/2024] [Accepted: 02/28/2024] [Indexed: 03/05/2024]
Abstract
Extensive experimental evidence points to neuroinflammation and oxidative stress as major pathogenic events that initiate and drive the neurodegenerative process. Monosodium glutamate (MSG) is a widely used food additive in processed foods known for its umami taste-enhancing properties. However, concerns about its potential adverse effects on the brain have been raised. Thus, the present study investigated the impact of MSG on lipopolysaccharide (LPS)-induced neurotoxicity in rat brains. Wistar rats weighing between 180 g and 200 g were randomly allocated into four groups: control (received distilled water), MSG (received 1.5 g/kg/day), LPS (received 250 µg/kg/day), and LPS + MSG (received LPS, 250 µg/kg, and MSG, 1.5 g/kg). LPS was administered intraperitoneally for 7 days while MSG was administered orally for 14 days. Our results showed that MSG exacerbated LPS-induced impairment in locomotor and exploratory activities in rats. Similarly, MSG exacerbated LPS-induced oxidative stress as evidenced by increased levels of malondialdehyde (MDA) with a concomitant decrease in levels of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and glutathione-s-transferase (GST) in the brain tissue. In addition, MSG potentiated LPS-induced neuroinflammation, as indicated by increased levels of pro-inflammatory cytokines such as interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) as well as myeloperoxidase (MPO) and nitric oxide (NO) in the brain. Moreover, MSG aggravated LPS-induced cholinergic dysfunction, as demonstrated by increased activity of acetylcholinesterase (AChE) in the brain. Further, we found a large number of degenerative neurons widespread in hippocampal CA1, CA3 regions, cerebellum, and cortex according to H&E staining. Taken together, our findings suggest that MSG aggravates LPS-induced neurobehavioral deficits, oxidative stress, neuroinflammation, cholinergic dysfunction, and neurodegeneration in rat brains.
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Affiliation(s)
- Folake Olubukola Asejeje
- Department of Chemical Sciences, Faculty of Natural Sciences, Ajayi Crowther University, Oyo, Nigeria.
| | - Michael Abayomi Abiola
- Department of Chemical Sciences, Faculty of Natural Sciences, Ajayi Crowther University, Oyo, Nigeria; Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Oluwatobi Adewumi Adeyemo
- Department of Chemical Sciences, Faculty of Natural Sciences, Ajayi Crowther University, Oyo, Nigeria
| | | | - Abayomi Mayowa Ajayi
- Department of Pharmacology and Therapeutics, Faculty of Basic Medical Sciences, University of Ibadan, Ibadan, Nigeria
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Lin Q, Chen L, Zheng H, Tan H, Zhang G, Zheng W. Imaging of nerve injury in neonatal acute bilirubin encephalopathy using 1H-MRS and Glu-CEST techniques. Front Neurosci 2023; 17:1110349. [PMID: 37056307 PMCID: PMC10086169 DOI: 10.3389/fnins.2023.1110349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 02/23/2023] [Indexed: 03/30/2023] Open
Abstract
ObjectivesTo investigate the significance of proton magnetic resonance spectroscopy (1H-MRS) and glutamate chemical exchange saturation transfer (Glu-CEST) techniques in assessing the condition and prognosis of acute bilirubin encephalopathy patients and to understand the mechanism of nerve injury in this disease.Materials and methodsFrom September 2019 to February 2021, 31 neonates with acute bilirubin encephalopathy and 16 healthy neonates were enrolled in this study. All the quantitative results of 1H-MRS, Glu-CEST, and conventional magnetic resonance imaging (MRI) of all neonates were analyzed. The associations between statistically significant indicators of imaging and developmental quotients (DQ) were analyzed.ResultsThe 31 cases were assigned to the mild subgroup (n = 21) and moderate and severe subgroup (n = 10) according to the bilirubin-induced neurologic dysfunction (BIND) scores. The case group had elevated Cho and GABA absolute concentrations compared to the normal control group (all p < 0.05). Compared with the normal control group, the absolute concentration of GABA of the moderate and severe subgroup was significantly larger (p < 0.05). Compared with the normal control group, the Glu-CEST% values in the left basal ganglia, right thalamus, left frontal cortex and bilateral medial geniculate body of the case group was significantly larger (all p < 0.05). The moderate and severe subgroup had higher Glu-CEST% values in the left basal ganglia, right thalamus, and bilateral medial geniculate body than the normal control group (all p < 0.05). A negative association was revealed between the DQ scores and the Glu-CEST% values in the left basal ganglia (r = −0.888, p < 0.05).ConclusionThe combination of 1H-MRS and Glu-CEST techniques can monitor the intracerebral metabolite level of acute bilirubin encephalopathy and evaluate the illness severity.
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Affiliation(s)
- Qihuan Lin
- Imaging Center, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Lanmei Chen
- Department of Radiology, The Second Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, China
| | - Hongyi Zheng
- Department of Radiology, The Second Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, China
| | - Hui Tan
- Department of Radiology, The Second Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, China
| | - Gengbiao Zhang
- Department of Radiology, The Second Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, China
| | - Wenbin Zheng
- Department of Radiology, The Second Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong, China
- *Correspondence: Wenbin Zheng,
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Abu-Elfotuh K, Abdel-Sattar SA, Abbas AN, Mahran YF, Alshanwani AR, Hamdan AME, Atwa AM, Reda E, Ahmed YM, Zaghlool SS, El-Din MN. The protective effect of thymoquinone or/and thymol against monosodium glutamate-induced attention-deficit/hyperactivity disorder (ADHD)-like behavior in rats: Modulation of Nrf2/HO-1, TLR4/NF-κB/NLRP3/caspase-1 and Wnt/β-Catenin signaling pathways in rat model. Biomed Pharmacother 2022; 155:113799. [PMID: 36271575 DOI: 10.1016/j.biopha.2022.113799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 09/28/2022] [Accepted: 10/02/2022] [Indexed: 11/26/2022] Open
Abstract
Both thymoquinone (TQ) and thymol (T) have been proved to possess a positive impact on human health. In this research, we aimed to investigate the effect of these compounds separately and together on the Attention-deficit/hyperactivity disorder (ADHD)-like behavior induced by monosodium glutamate (MSG) in rats. Forty male, Spargue Dawley rat pups (postnatal day 21), were randomly allocated into five groups: Normal saline (NS), MSG, MSG+TQ, MSG+T, and MSG+TQ+T. MSG (0.4 mg/kg/day), TQ (10 mg/kg/day) and T (30 mg/kg/day) were orally administered for 8 weeks. The behavioral tests proved that rats treated with TQ and/or T showed improved locomotor, attention and cognitive functions compared to the MSG group with more pronounced effect displayed with their combination. All treated groups showed improvement in MSG-induced aberrations in brain levels of GSH, IL-1β, TNF-α, GFAP, glutamate, calcium, dopamine, norepinephrine, Wnt3a, β-Catenin and BDNF. TQ and/or T treatment also enhanced the mRNA expression of Nrf2, HO-1 and Bcl2 while reducing the protein expression of TLR4, NFκB, NLRP3, caspase 1, Bax, AIF and GSK3β as compared to the MSG group. However, the combined therapy showed more significant effects in all measured parameters. All of these findings were further confirmed by the histopathological examinations. Current results concluded that the combined therapy of TQ and T had higher protective effects than their individual supplementations against MSG-induced ADHD-like behavior in rats.
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de Fraga LS, Tassinari ID, Jantsch J, Guedes RP, Bambini-Junior V. 'A picture is worth a thousand words': The use of microscopy for imaging neuroinflammation. Clin Exp Immunol 2021; 206:325-345. [PMID: 34596237 DOI: 10.1111/cei.13669] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 01/08/2023] Open
Abstract
Since the first studies of the nervous system by the Nobel laureates Camillo Golgi and Santiago Ramon y Cajal using simple dyes and conventional light microscopes, microscopy has come a long way to the most recent techniques that make it possible to perform images in live cells and animals in health and disease. Many pathological conditions of the central nervous system have already been linked to inflammatory responses. In this scenario, several available markers and techniques can help imaging and unveil the neuroinflammatory process. Moreover, microscopy imaging techniques have become even more necessary to validate the large quantity of data generated in the era of 'omics'. This review aims to highlight how to assess neuroinflammation by using microscopy as a tool to provide specific details about the cell's architecture during neuroinflammatory conditions. First, we describe specific markers that have been used in light microscopy studies and that are widely applied to unravel and describe neuroinflammatory mechanisms in distinct conditions. Then, we discuss some important methodologies that facilitate the imaging of these markers, such as immunohistochemistry and immunofluorescence techniques. Emphasis will be given to studies using two-photon microscopy, an approach that revolutionized the real-time assessment of neuroinflammatory processes. Finally, some studies integrating omics with microscopy will be presented. The fusion of these techniques is developing, but the high amount of data generated from these applications will certainly improve comprehension of the molecular mechanisms involved in neuroinflammation.
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Affiliation(s)
- Luciano Stürmer de Fraga
- Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.,Centro de Pesquisa Experimental, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil
| | - Isadora D'Ávila Tassinari
- Programa de Pós-Graduação em Ciências Biológicas: Fisiologia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.,Centro de Pesquisa Experimental, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil
| | - Jeferson Jantsch
- Programa de Pós-Graduação em Biociências, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Brazil
| | - Renata Padilha Guedes
- Programa de Pós-Graduação em Biociências, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Brazil
| | - Victorio Bambini-Junior
- School of Pharmacy and Biomedical Sciences, University of Central Lancashire (UCLan), Preston, UK
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Selective activation of metabotropic glutamate receptor 7 blocks paclitaxel-induced acute neuropathic pain and suppresses spinal glial reactivity in rats. Psychopharmacology (Berl) 2021; 238:107-119. [PMID: 33089875 DOI: 10.1007/s00213-020-05662-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 09/10/2020] [Indexed: 12/30/2022]
Abstract
RATIONALE Paclitaxel-induced acute pain syndrome (P-APS), characterized by deep muscle aches and arthralgia, occurs in more than 70% of patients who receive paclitaxel. P-APS can be debilitating for patients and lead to reductions and discontinuation of potentially curable therapy. Despite being relatively common in clinical practice, no clear treatment exists for P-APS and the underlying mechanisms remain poorly defined. Regulation of glutamatergic transmission by metabotropic glutamate receptors (mGluRs) has received growing attention with respect to its role in neuropathic pain. To our knowledge, no study has been conducted on alterations and functions of group III mGluR7 signaling in P-APS. OBJECTIVES In the present study, we determined whether a single administration of paclitaxel induces glutamatergic alterations and whether mGluR7 activation blocks paclitaxel-induced neuropathic pain by suppressing glial reactivity in the spinal cord. RESULTS A single paclitaxel injection dose-dependently induced acute mechanical and thermal hypersensitivity, and was associated with increased glutamate level accompanied by reduction in mGluR7 expression in the spinal cord. Selective activation of mGluR7 by its positive allosteric modulator, AMN082, blocked the development of paclitaxel-induced acute mechanical and thermal hypersensitivity, without affecting the normal pain behavior of control rats. Moreover, activation of mGluR7 by AMN082 inhibited glial reactivity and decreased pro-inflammatory cytokine release during P-APS. Abortion of spinal glial reaction to paclitaxel alleviated paclitaxel-induced acute mechanical and thermal hypersensitivity. CONCLUSIONS There results support the hypothesis that spinal mGluR7 signaling plays an important role in P-APS; Selective activation of mGluR7 by its positive allosteric modulator, AMN082, blocks P-APS in part by reducing spinal glial reactivity and neuroinflammatory process.
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Castañeda-Cabral JL, López-Ortega JG, Fajardo-Fregoso BF, Beas-Zárate C, Ureña-Guerrero ME. Glutamate induced neonatal excitotoxicity modifies the expression level of EAAT1 (GLAST) and EAAT2 (GLT-1) proteins in various brain regions of the adult rat. Neurosci Lett 2020; 735:135237. [PMID: 32645399 DOI: 10.1016/j.neulet.2020.135237] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 07/03/2020] [Accepted: 07/04/2020] [Indexed: 02/08/2023]
Abstract
Glutamate-mediated excitatory synaptic signalling is primarily controlled by excitatory amino acid transporters (EAATs), such as EAAT1 and EAAT2, which are located mostly on astrocytes and, together, uptake more than 95 % of extracellular glutamate. Alterations in the functional expression levels of EAATs can lead to excessive extracellular glutamate accumulation, potentially triggering excitotoxicity and seizures, among other neurological disorders. Excitotoxicity induced in early developmental stages can lead to lasting changes in several neurotransmission systems, including the glutamatergic system, which could make the brain more susceptible to a second insult. In this study, the expression levels of EAAT1 (GLAST) and EAAT2 (GLT-1) proteins were assessed in the cerebral motor cortex (CMC), striatum, hippocampus and entorhinal cortex (EC) of male adult rats following the neonatal excitotoxic process triggered by monosodium glutamate (MSG)-treatment (4 g/kg of body weight at postnatal days 1,3,5 and 7, subcutaneously). Western blot analysis showed that neonatal MSG-treatment decreased EAAT1 expression levels in the CMC, striatum and hippocampus, while EAAT2 levels were increased in the striatum and EC and decreased in the CMC. Immunofluorescence staining confirmed the changes in EAAT1 and EAAT2 expression induced by neonatal MSG-treatment, which were accompanied by an increase in the glial fibrillary acidic protein (GFAP) immunofluorescence signalthat was particularly significant in the hippocampus. Our results show that a neonatal excitotoxic processes can induce lasting changes in the expression levels of EAAT1 and EAAT2 proteins and suggest that although astrogliosis occurs, glutamate uptake could be deficient, particularly in the CMC and hippocampus.
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Affiliation(s)
- José Luis Castañeda-Cabral
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias (CUCBA), Universidad de Guadalajara, Zapopan, Jalisco, Mexico
| | - José Guadalupe López-Ortega
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias (CUCBA), Universidad de Guadalajara, Zapopan, Jalisco, Mexico
| | - Blanca Fabiola Fajardo-Fregoso
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias (CUCBA), Universidad de Guadalajara, Zapopan, Jalisco, Mexico
| | - Carlos Beas-Zárate
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias (CUCBA), Universidad de Guadalajara, Zapopan, Jalisco, Mexico
| | - Mónica E Ureña-Guerrero
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias (CUCBA), Universidad de Guadalajara, Zapopan, Jalisco, Mexico.
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Onaolapo AY, Onaolapo OJ. Dietary glutamate and the brain: In the footprints of a Jekyll and Hyde molecule. Neurotoxicology 2020; 80:93-104. [PMID: 32687843 DOI: 10.1016/j.neuro.2020.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/29/2020] [Accepted: 07/14/2020] [Indexed: 12/15/2022]
Abstract
Glutamate is a crucial neurotransmitter of the mammalian central nervous system, a molecular component of our diet, and a popular food-additive. However, for decades, concerns have been raised about the issue of glutamate's safety as a food additive; especially, with regards to its ability (or otherwise) to cross the blood-brain barrier, cause excitotoxicity, or lead to neuron death. Results of animal studies following glutamate administration via different routes suggest that an array of effects can be observed. While some of the changes appear deleterious, some are not fully-understood, and the impact of others might even be beneficial. These observations suggest that with regards to the mammalian brain, exogenous glutamate might exert a double-sided effect, and in essence be a two-faced molecule whose effects may be dependent on several factors. This review draws from the research experiences of the authors and other researchers regarding the effects of exogenous glutamate on the brain of rodents. We also highlight the possible implications of such effects on the brain, in health and disease. Finally, we deduce that beyond the culinary effects of exogenous glutamate, there is the possibility of a beneficial role in the understanding and management of brain disorders.
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Affiliation(s)
- Adejoke Y Onaolapo
- Behavioural Neuroscience/Neurobiology Unit, Department of Anatomy, Ladoke Akintola University of Technology, Ogbomosho, Oyo State, Nigeria.
| | - Olakunle J Onaolapo
- Behavioural Neuroscience/Neuropharmacology Unit, Department of Pharmacology, Ladoke Akintola University of Technology, Osogbo, Osun State, Nigeria.
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Yang F, Zhu W, Cai X, Zhang W, Yu Z, Li X, Zhang J, Cai M, Xiang J, Cai D. Minocycline alleviates NLRP3 inflammasome-dependent pyroptosis in monosodium glutamate-induced depressive rats. Biochem Biophys Res Commun 2020; 526:553-559. [PMID: 32245616 DOI: 10.1016/j.bbrc.2020.02.149] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 02/24/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND Inflammasome activation and followed by the release of proinflammatory cytokines play a pivotal role in the development and progression of depression. However, the involvement of gasdermin D (GSDMD)-mediated pyroptosis in inflammasome-associated depression has not been studied. The present study aimed to determine the involvement of pyroptosis in the development of depression. METHODS The rat depressive model was established by the administration of monosodium glutamate (MSG) in postnatal rats. Minocycline (an anti-inflammatory agent) and VX-765 (a specific inhibitor of caspase-1) were given as intervention treatments when rats were two-month-old. Rat depressive behaviors were evaluated by behavioral tests, including open field test, sucrose preference test, and forced swim test. Rat hippocampi were collected for western blotting and immunofluorescence examination. RESULTS MSG administration induced depressive-like behavior in rats. MSG upregulated protein presences of caspase-1, GSDMD, interleukin-1β (IL-1β), interleukin-18 (IL-18), NLR pyrin domain-containing 3 (NLRP3), apoptosis-associated speck-like protein (ASC), high mobility group box 1 protein (HMGB1), and the receptor for advanced glycation end products (RAGE) in the hippocampus. Protein presences of HMGB1, NLRP3 and GSDMD were upregulated in Olig2+ oligodendrocytes in the hippocampus. The data suggest that both HMGB1/RAGE/NLRP3 signalings and GSDMD-dependent pyroptosis were activated. Both minocycline and VX-765 treatments improved depressive-like behaviors. Minocycline treatment significantly reduced both HMGB1/RAGE/NLRP3 inflammasome signalings and GSDMD-dependent pyroptosis. VX-765 downregulated GSDMD-dependent pyroptosis, but not HMGB1/RAGE signalings, indicating that GSDMD-dependent pyroptosis is a key player in the progress of depression. CONCLUSION In rats hippocampus, NLRP3 inflammasome activates GSDMD mediated-pyroptosis in the hippocampus of MSG-induced depressive rats.
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Affiliation(s)
- Feng Yang
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, China; Institute of Neurology, Academy of Integrative Medicine, Fudan University, Shanghai, China
| | - Wen Zhu
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, China; Institute of Neurology, Academy of Integrative Medicine, Fudan University, Shanghai, China
| | - Xiaofang Cai
- Department of Traditional Chinese Medicine, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University, China
| | - Wen Zhang
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, China; Institute of Neurology, Academy of Integrative Medicine, Fudan University, Shanghai, China
| | - Zhonghai Yu
- Department of Traditional Chinese Medicine, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University, China
| | - Xiangting Li
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, China; Institute of Neurology, Academy of Integrative Medicine, Fudan University, Shanghai, China
| | - Jingsi Zhang
- Department of Neurology, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, China
| | - Min Cai
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, China; Institute of Neurology, Academy of Integrative Medicine, Fudan University, Shanghai, China
| | - Jun Xiang
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, China; Institute of Neurology, Academy of Integrative Medicine, Fudan University, Shanghai, China.
| | - Dingfang Cai
- Department of Integrative Medicine, Zhongshan Hospital, Fudan University, China; Institute of Neurology, Academy of Integrative Medicine, Fudan University, Shanghai, China.
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Hernandez-Ojeda M, Ureña-Guerrero ME, Gutierrez-Barajas PE, Cardenas-Castillo JA, Camins A, Beas-Zarate C. KB-R7943 reduces 4-aminopyridine-induced epileptiform activity in adult rats after neuronal damage induced by neonatal monosodium glutamate treatment. J Biomed Sci 2017; 24:27. [PMID: 28486943 PMCID: PMC5423021 DOI: 10.1186/s12929-017-0335-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 05/03/2017] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Neonatal monosodium glutamate (MSG) treatment triggers excitotoxicity and induces a degenerative process that affects several brain regions in a way that could lead to epileptogenesis. Na+/Ca2+ exchangers (NCX1-3) are implicated in Ca2+ brain homeostasis; normally, they extrude Ca2+ to control cell inflammation, but after damage and in epilepsy, they introduce Ca2+ by acting in the reverse mode, amplifying the damage. Changes in NCX3 expression in the hippocampus have been reported immediately after neonatal MSG treatment. In this study, the expression level of NCX1-3 in the entorhinal cortex (EC) and hippocampus (Hp); and the effects of blockade of NCXs on the seizures induced by 4-Aminopyridine (4-AP) were analysed in adult rats after neonatal MSG treatment. KB-R7943 was applied as NCXs blocker, but is more selective to NCX3 in reverse mode. METHODS Neonatal MSG treatment was applied to newborn male rats at postnatal days (PD) 1, 3, 5, and 7 (4 g/kg of body weight, s.c.). Western blot analysis was performed on total protein extracts from the EC and Hp to estimate the expression level of NCX1-3 proteins in relative way to the expression of β-actin, as constitutive protein. Electrographic activity of the EC and Hp were acquired before and after intracerebroventricular (i.c.v.) infusion of 4-AP (3 nmol) and KB-R7943 (62.5 pmol), alone or in combination. All experiments were performed at PD60. Behavioural alterations were also recorder. RESULTS Neonatal MSG treatment significantly increased the expression of NCX3 protein in both studied regions, and NCX1 protein only in the EC. The 4-AP-induced epileptiform activity was significantly higher in MSG-treated rats than in controls, and KB-R7943 co-administered with 4-AP reduced the epileptiform activity in more prominent way in MSG-treated rats than in controls. CONCLUSIONS The long-term effects of neonatal MSG treatment include increases on functional expression of NCXs (mainly of NCX3) in the EC and Hp, which seems to contribute to improve the control that KB-R7943 exerted on the seizures induced by 4-AP in adulthood. The results obtained here suggest that the blockade of NCXs could improve seizure control after an excitotoxic process; however, this must be better studied.
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Affiliation(s)
- Mariana Hernandez-Ojeda
- Laboratorio de Biología de la Neurotransmisión, Edificio de Posgrado, Departamento de Biología Celular y Molecular, CUCBA, Universidad de Guadalajara, Km 15.5 Carretera a Nogales, Camino Ing. Ramón Padilla Sánchez Km 2, Zapopan, Jalisco Mexico 45221
| | - Monica E. Ureña-Guerrero
- Laboratorio de Biología de la Neurotransmisión, Edificio de Posgrado, Departamento de Biología Celular y Molecular, CUCBA, Universidad de Guadalajara, Km 15.5 Carretera a Nogales, Camino Ing. Ramón Padilla Sánchez Km 2, Zapopan, Jalisco Mexico 45221
| | - Paola E. Gutierrez-Barajas
- Laboratorio de Biología de la Neurotransmisión, Edificio de Posgrado, Departamento de Biología Celular y Molecular, CUCBA, Universidad de Guadalajara, Km 15.5 Carretera a Nogales, Camino Ing. Ramón Padilla Sánchez Km 2, Zapopan, Jalisco Mexico 45221
| | - Jazmin A. Cardenas-Castillo
- Laboratorio de Biología de la Neurotransmisión, Edificio de Posgrado, Departamento de Biología Celular y Molecular, CUCBA, Universidad de Guadalajara, Km 15.5 Carretera a Nogales, Camino Ing. Ramón Padilla Sánchez Km 2, Zapopan, Jalisco Mexico 45221
| | - Antoni Camins
- Unitat de Farmacologia i Farmacognòsia, Institut de Neurociencias, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
- Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Carlos Beas-Zarate
- Laboratorio de Biología de la Neurotransmisión, Edificio de Posgrado, Departamento de Biología Celular y Molecular, CUCBA, Universidad de Guadalajara, Km 15.5 Carretera a Nogales, Camino Ing. Ramón Padilla Sánchez Km 2, Zapopan, Jalisco Mexico 45221
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Foran L, Blackburn K, Kulesza RJ. Auditory hindbrain atrophy and anomalous calcium binding protein expression after neonatal exposure to monosodium glutamate. Neuroscience 2017; 344:406-417. [DOI: 10.1016/j.neuroscience.2017.01.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 12/31/2016] [Accepted: 01/03/2017] [Indexed: 01/29/2023]
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11
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Onaolapo OJ, Onaolapo AY, Akanmu MA, Gbola O. Evidence of alterations in brain structure and antioxidant status following 'low-dose' monosodium glutamate ingestion. ACTA ACUST UNITED AC 2016; 23:147-56. [PMID: 27312658 DOI: 10.1016/j.pathophys.2016.05.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 05/09/2016] [Accepted: 05/19/2016] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The study investigated the effects of low dose monosodium glutamate (MSG) on the brain, with a view to providing information on its effects on neuronal morphology and antioxidant status in mice. METHODOLOGY Sixty male mice (20-22 g) were divided into six groups of ten animals each. Vehicle (distilled water), a standard (l-glutamate at 10mg/kg body weight) or MSG (10, 20, 40 and 80mg/kg body weight) were administered orally for 28days. Sections of the cerebrum, hippocampus and cerebellum were processed and stained using hematoxylin and eosin, examined under a microscope and captured images analysed. Plasma and brain levels of glutamate, glutamine, and antioxidants were assayed. Data obtained were analysed using descriptive and inferential statistics. RESULTS MSG ingestion did not significantly alter body weight. Relative brain weight increased at 40 and 80mg/kg compared to vehicle. Histological and histomorphometric changes consistent with neuronal damage were seen in the cerebrum, hippocampus and cerebellum at 40 and 80mg/kg. Plasma glutamate and glutamine assay showed significant increase at 40 and 80mg/kg while no significant difference in total brain glutamate or glutamine levels were seen. Levels of brain superoxide dismutase and catalase decreased with increasing doses of MSG, while nitric oxide (NO) increased at these doses. CONCLUSION The study showed morphological alterations consistent with neuronal injury, biochemical changes of oxidative stress and a rise in plasma glutamate and glutamine. These data therefore still support the need for cautious consideration in the indiscriminate use of MSG as a dietary flavor enhancer.
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Affiliation(s)
- Olakunle James Onaolapo
- Department of Pharmacology, Faculty of Basic Medical Sciences, College of Health Sciences, Ladoke Akintola University of Technology, Osogbo, Osun State, Nigeria; Department of Pharmacology, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria.
| | - Adejoke Yetunde Onaolapo
- Department of Human Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, Ladoke Akintola University of Technology, Ogbomosho, Oyo State, Nigeria
| | - M A Akanmu
- Department of Pharmacology, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
| | - Olayiwola Gbola
- Department of Clinical Pharmacy, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
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Rojas-Castañeda JC, Vigueras-Villaseñor RM, Chávez-Saldaña M, Rojas P, Gutiérrez-Pérez O, Rojas C, Arteaga-Silva M. Neonatal exposure to monosodium glutamate induces morphological alterations in suprachiasmatic nucleus of adult rat. Int J Exp Pathol 2016; 97:18-26. [PMID: 26799547 PMCID: PMC4840248 DOI: 10.1111/iep.12157] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 10/07/2015] [Indexed: 01/19/2023] Open
Abstract
Neonatal exposure to monosodium glutamate (MSG) induces circadian disorders in several physiological and behavioural processes regulated by the suprachiasmatic nucleus (SCN). The objective of this study was to evaluate the effects of neonatal exposure to MSG on locomotor activity, and on morphology, cellular density and expression of proteins, as evaluated by optical density (OD), of vasopressin (VP)-, vasoactive intestinal polypeptide (VIP)- and glial fibrillary acidic protein (GFAP)-immunoreactive cells in the SCN. Male Wistar rats were used: the MSG group was subcutaneously treated from 3 to 10 days of age with 3.5 mg/g/day. Locomotor activity was evaluated at 90 days of age using 'open-field' test, and the brains were processed for immunohistochemical studies. MSG exposure induced a significant decrease in locomotor activity. VP- and VIP-immunoreactive neuronal densities showed a significant decrease, while the somatic OD showed an increase. Major axes and somatic area were significantly increased in VIP neurons. The cellular and optical densities of GFAP-immunoreactive sections of SCN were significantly increased. These results demonstrated that newborn exposure to MSG induced morphological alterations in SCN cells, an alteration that could be the basis for behavioural disorders observed in the animals.
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Affiliation(s)
| | - Rosa María Vigueras-Villaseñor
- Subdirección de Medicina Experimental, Instituto Nacional de Pediatría, México D.F., México
- Departamento de Morfología, Facultad de Medicina Veterinaria y Zootécnia, UNAM, México D.F., México
| | | | - Patricia Rojas
- Laboratorio de Neurotoxicología, Instituto Nacional de Neurología y Neurocirugía, 'Manuel Velasco Suárez', México D.F., México
| | - Oscar Gutiérrez-Pérez
- Subdirección de Medicina Experimental, Instituto Nacional de Pediatría, México D.F., México
- Departamento de Morfología, Facultad de Medicina Veterinaria y Zootécnia, UNAM, México D.F., México
| | - Carolina Rojas
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, UNAM, México D.F., México
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Hacimuftuoglu A, Tatar A, Cetin D, Taspinar N, Saruhan F, Okkay U, Turkez H, Unal D, Stephens RL, Suleyman H. Astrocyte/neuron ratio and its importance on glutamate toxicity: an in vitro voltammetric study. Cytotechnology 2015; 68:1425-33. [PMID: 26438331 DOI: 10.1007/s10616-015-9902-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 07/09/2015] [Indexed: 01/05/2023] Open
Abstract
The purpose of this study was to clarify the relationship between neuron cells and astrocyte cells in regulating glutamate toxicity on the 10th and 20th day in vitro. A mixed primary culture system from newborn rats that contain cerebral cortex neurons cells was employed to investigate the glutamate toxicity. All cultures were incubated with various glutamate concentrations, then viability tests and histological analyses were performed. The activities of glutamate transporters were determined by using in vitro voltammetry technique. Viable cell number was decreased significantly on the 10th day at 10(-7) M and at 10(-6) M glutamate applications, however, viable cell number was not decreased at 20th day. Astrocyte number was increased nearly six times on the 20th day as compared to the 10th day. The peak point of glutamate reuptake capacity was about 2 × 10(-4) M on the 10th day and 10(-3) M on the 20th day. According to our results, we suggested that astrocyte age was important to maintain neuronal survival against glutamate toxicity. Thus, we revealed activation or a trigger point of glutamate transporters on astrocytes due to time since more glutamate was taken up by astrocytes when glutamate transporters on the astrocyte were triggered with high exogenous glutamate concentrations. In conclusion, the present investigation is the first voltammetric study on the reuptake parameters of glutamate in vitro.
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Affiliation(s)
- Ahmet Hacimuftuoglu
- Department of Medical Pharmacology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.
| | - Abdulgani Tatar
- Department of Medical Genetics, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Damla Cetin
- Department of Medical Pharmacology, Faculty of Medicine, Kafkas University, Kars, Turkey
| | - Numan Taspinar
- Department of Medical Pharmacology, Faculty of Medicine, Atatürk University, Erzurum, Turkey
| | - Fatih Saruhan
- Department of Medical Pharmacology, Faculty of Medicine, Atatürk University, Erzurum, Turkey
| | - Ufuk Okkay
- Department of Medical Pharmacology, Faculty of Medicine, Atatürk University, Erzurum, Turkey
| | - Hasan Turkez
- Department of Molecular Biology and Genetics, Faculty of Sciences, Erzurum Technical University, Erzurum, Turkey.,Department of Pharmaceutical Sciences, University of "G. D'Annunzio", Chieti, Italy
| | - Deniz Unal
- Department of Histology, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Robert Louis Stephens
- Department of Physiology and Cell Biology, Medical College, The Ohio State University, Columbus, OH, USA
| | - Halis Suleyman
- Department of Medical Pharmacology, Faculty of Medicine, Erzincan University, Erzincan, Turkey
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Gudiño-Cabrera G, Ureña-Guerrero ME, Rivera-Cervantes MC, Feria-Velasco AI, Beas-Zárate C. Excitotoxicity triggered by neonatal monosodium glutamate treatment and blood-brain barrier function. Arch Med Res 2014; 45:653-9. [PMID: 25431840 DOI: 10.1016/j.arcmed.2014.11.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 11/13/2014] [Indexed: 12/21/2022]
Abstract
It is likely that monosodium glutamate (MSG) is the excitotoxin that has been most commonly employed to characterize the process of excitotoxicity and to improve understanding of the ways that this process is related to several pathological conditions of the central nervous system. Excitotoxicity triggered by neonatal MSG treatment produces a significant pathophysiological impact on adulthood, which could be due to modifications in the blood-brain barrier (BBB) permeability and vice versa. This mini-review analyzes this topic through brief descriptions about excitotoxicity, BBB structure and function, role of the BBB in the regulation of Glu extracellular levels, conditions that promote breakdown of the BBB, and modifications induced by neonatal MSG treatment that could alter the behavior of the BBB. In conclusion, additional studies to better characterize the effects of neonatal MSG treatment on excitatory amino acids transporters, ionic exchangers, and efflux transporters, as well as the role of the signaling pathways mediated by erythropoietin and vascular endothelial growth factor in the cellular elements of the BBB, should be performed to identify the mechanisms underlying the increase in neurovascular permeability associated with excitotoxicity observed in several diseases and studied using neonatal MSG treatment.
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Affiliation(s)
- Graciela Gudiño-Cabrera
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Zapopan, Jalisco, México
| | - Monica E Ureña-Guerrero
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Zapopan, Jalisco, México
| | - Martha C Rivera-Cervantes
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Zapopan, Jalisco, México
| | - Alfredo I Feria-Velasco
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Zapopan, Jalisco, México
| | - Carlos Beas-Zárate
- Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Zapopan, Jalisco, México; División de Neurociencias, CIBO, IMSS, Guadalajara, Jalisco, México.
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15
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Hamasaki MY, Hirata MH, Hirata RDC, Himelfarb ST, Campos LMG, Nogueira MI. [Analysis of the mRNA expression of the S100β protein in adipocytes of patients with diabetes mellitus, type 2]. ACTA ACUST UNITED AC 2013; 56:435-40. [PMID: 23108748 DOI: 10.1590/s0004-27302012000700005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 08/30/2012] [Indexed: 11/22/2022]
Abstract
OBJECTIVE This study aims to explore the possible relationship between the expression level of S100β protein mRNA with diabetes mellitus type 2 in adipocytes from patients with this disease in comparison with normoglycemic individuals. MATERIALS AND METHODS Samples of adipose tissue of eight patients from the coronary section of the Institute Dante Pazzanese of Cardiology (IDPC), four in Group Diabetes and four of Normoglycemic group, were evaluated by RT-PCR real time. RESULTS An increase around 15 times values, between the threshold cycle (ΔCt), of mRNA expression of S100β protein in adipocytes of the diabetes group was observed in comparison to the control group (p = 0.015). CONCLUSION Our results indicate, for the first time, that there is coexistence of increased expression of the S100β and the type 2 diabetes mellitus gene.
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Affiliation(s)
- Mike Yoshio Hamasaki
- Laboratório de Neurociências, Departamento de Anatomia, Instituto de Ciências Biomédicas III, Universidade de São Paulo, São Paulo, SP, Brasil
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Berger J, Dumont A, Focant M, Vergouts M, Sternotte A, Calas AG, Goursaud S, Hermans E. Opposite regulation of metabotropic glutamate receptor 3 and metabotropic glutamate receptor 5 by inflammatory stimuli in cultured microglia and astrocytes. Neuroscience 2012; 205:29-38. [DOI: 10.1016/j.neuroscience.2011.12.044] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 12/13/2011] [Accepted: 12/23/2011] [Indexed: 01/09/2023]
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17
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HIF-1α expression in the hippocampus and peripheral macrophages after glutamate-induced excitotoxicity. J Neuroimmunol 2011; 238:12-8. [DOI: 10.1016/j.jneuroim.2011.06.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2010] [Revised: 05/30/2011] [Accepted: 06/01/2011] [Indexed: 01/13/2023]
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Medina-Ceja L, Sandoval-García F, Pardo-Peña K. Effect of Early Glutamate Exposure on EAAT-3 and GAT-1 Protein Expression in Cells of the Dentate Gyrus and CA1 Region of the Adult Rat Hippocampus. Arch Med Res 2011; 42:433-8. [DOI: 10.1016/j.arcmed.2011.08.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Accepted: 08/10/2011] [Indexed: 10/17/2022]
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Ortuño-Sahagún D, Rivera-Cervantes MC, Gudiño-Cabrera G, Junyent F, Verdaguer E, Auladell C, Pallàs M, Camins A, Beas-Zárate C. Microarray analysis of rat hippocampus exposed to excitotoxicity: reversal Na(+)/Ca(2+) exchanger NCX3 is overexpressed in glial cells. Hippocampus 2010; 22:128-40. [PMID: 20928830 DOI: 10.1002/hipo.20869] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2010] [Indexed: 02/06/2023]
Abstract
Multiple factors are involved in the glutamate-induced excitotoxicity phenomenon, such as overload of ionotropic and metabotropic receptors, excess Ca(2+) influx, nitric oxide synthase activation, oxidative damage due to increase in free radicals, and release of endogenous polyamine, among others. In order to attempt a more integrated approach to address this issue, we established, by microarray analysis, the hippocampus gene expression profiles under glutamate-induced excitotoxicity conditions. Increased gene expression is mainly related to excitotoxicity (CaMKII, glypican 2, GFAP, NCX3, IL-2, and Gmeb2) or with cell damage response (dynactin and Ecel1). Several genes that augmented their expression are related to glutamatergic system modulation, in particular with NMDA receptor modulation and calcium homeostasis (IL-2, CaMKII, acrosin, Gmeb2, hAChE, Slc83a, and SP1 factor). Conversely, among genes that diminished their expression, we found the Syngap 1, which is downregulated by CaMKII, and the MHC II, which is downregulated by glutamate. Changes observed in gene expression induced by monosodium glutamate (MSG) neonatal treatment in the hippocampus are consistent with the activation of the mechanisms that modulate NMDA receptor function as well as with the implementation of plastic response to cell damage and intracellular calcium homeostasis. Regarding this aspect, we report here that NCX3/Slc8a3, a Na(+)/Ca(2+) membrane exchanger, is highly expressed in astrocytes, both in vitro and in vivo, in response to glutamate-induced excitotoxicity. Hence, the results of this analysis present a broad view of the expression profile elicited by MSG neonatal treatment, and lead us to suggest the possible molecular pathways of action and reaction involved under this experimental model of excitotoxicity.
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Affiliation(s)
- Daniel Ortuño-Sahagún
- Laboratorio de Desarrollo y Regeneración Neural, Instituto de Neurobiología, C.U.C.B.A, Universidad de Guadalajara, Guadalajara, Jalisco, México
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20
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Shang YC, Chong ZZ, Hou J, Maiese K. Wnt1, FoxO3a, and NF-kappaB oversee microglial integrity and activation during oxidant stress. Cell Signal 2010; 22:1317-29. [PMID: 20462515 PMCID: PMC2893230 DOI: 10.1016/j.cellsig.2010.04.009] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Accepted: 04/29/2010] [Indexed: 01/08/2023]
Abstract
Elucidating the underlying mechanisms that govern microglial activation and survival is essential for the development of new treatment strategies for neurodegenerative disorders, since microglia serve not only as guardian sentries of the nervous system, but also play a significant role in determining neuronal and vascular cell fate. Here we show that endogenous and exogenous Wnt1 in inflammatory microglial cells is necessary for the prevention of apoptotic early membrane phosphatidylserine exposure and later DNA degradation, since blockade of Wnt1 signaling abrogates cell survival during oxidative stress. Wnt1 prevents apoptotic demise through the post-translational phosphorylation and maintenance of FoxO3a in the cytoplasm to inhibit an apoptotic cascade that relies upon the loss of mitochondrial membrane permeability, cytochrome c release, Bad phosphorylation, and activation of caspase 3 and caspase 1 as demonstrated by complimentary gene knockdown studies of FoxO3a. Furthermore, subcellular trafficking and gene knockdown studies of NF-kappaB p65 illustrate that microglial cell survival determined by Wnt1 during oxidative stress requires NF-kappaB p65. Our work highlights Wnt1 and the control of novel downstream transcriptional pathways as critical components for the oversight of nervous system microglial cells.
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Affiliation(s)
- Yan Chen Shang
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Zhao Zhong Chong
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Jinling Hou
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Kenneth Maiese
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201
- Departments of Neurology and Anatomy & Cell Biology, Wayne State University School of Medicine, Detroit, Michigan 48201
- Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan 48201
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan 48201
- Institute of Environmental Health Sciences, Wayne State University School of Medicine, Detroit, Michigan 48201
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López-Pérez SJ, Ureña-Guerrero ME, Morales-Villagrán A. Monosodium glutamate neonatal treatment as a seizure and excitotoxic model. Brain Res 2010; 1317:246-56. [DOI: 10.1016/j.brainres.2009.12.054] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 12/17/2009] [Accepted: 12/18/2009] [Indexed: 10/20/2022]
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Shang YC, Chong ZZ, Hou J, Maiese K. FoxO3a governs early microglial proliferation and employs mitochondrial depolarization with caspase 3, 8, and 9 cleavage during oxidant induced apoptosis. Curr Neurovasc Res 2010; 6:223-38. [PMID: 19807657 DOI: 10.2174/156720209789630302] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Accepted: 08/31/2009] [Indexed: 12/16/2022]
Abstract
Microglia of the central nervous system have a dual role in the ability to influence the survival of neighboring cells. During inflammatory cell activation, microglia can lead to the disposal of toxic cellular products and permit tissue regeneration, but microglia also may lead to cellular destruction with phagocytic removal. For these reasons, it is essential to elucidate not only the underlying pathways that control microglial activation and proliferation, but also the factors that determine microglial survival. In this regard, we investigated in the EOC 2 microglial cell line with an oxygen-glucose deprivation (OGD) injury model of oxidative stress the role of the "O" class forkhead transcription factor FoxO3a that in some scenarios is closely linked to immune system function. We demonstrate that FoxO3a is a necessary element in the control of early and late apoptotic injury programs that involve membrane phosphatidylserine externalization and nuclear DNA degradation, since transient knockdown of FoxO3a in microglia preserves cellular survival 24 hours following OGD exposure. However, prior to the onset of apoptotic injury, FoxO3a facilitates the activation and proliferation of microglia as early as 3 hours following OGD exposure that occurs in conjunction with the trafficking of the unphosphorylated and active post-translational form of FoxO3a from the cytoplasm to the cell nucleus. FoxO3a also can modulate apoptotic mitochondrial signal transduction pathways in microglia, since transient knockdown of FoxO3a prevents mitochondrial membrane depolarization as well as the release of cytochrome c during OGD. Control of this apoptotic cascade also extends to progressive caspase activation as early as 1 hour following OGD exposure. The presence of FoxO3a is necessary for the expression of cleaved (active) caspase 3, 8, and 9, since loss of FoxO3a abrogates the induction of caspase activity. Interestingly, elimination of FoxO3a reduced caspase 9 activity to a lesser extent than that noted with caspase 3 and 8 activities, suggesting that FoxO3a in relation to caspase 9 may be more reliant upon other signal transduction pathways potentially independent from caspase 3 and 8.
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Affiliation(s)
- Yan Chen Shang
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Ting KK, Brew BJ, Guillemin GJ. Effect of quinolinic acid on human astrocytes morphology and functions: implications in Alzheimer's disease. J Neuroinflammation 2009; 6:36. [PMID: 20003262 PMCID: PMC2797503 DOI: 10.1186/1742-2094-6-36] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Accepted: 12/10/2009] [Indexed: 02/06/2023] Open
Abstract
The excitotoxin quinolinic acid (QUIN) is synthesized through the kynurenine pathway (KP) by activated monocyte lineage cells. QUIN is likely to play a role in the pathogenesis of several major neuroinflammatory diseases including Alzheimer's disease (AD). The presence of reactive astrocytes, astrogliosis, increased oxidative stress and inflammatory cytokines are important pathological hallmarks of AD. We assessed the stimulatory effects of QUIN at low physiological to high excitotoxic concentrations in comparison with the cytokines commonly associated with AD including IFN-γ and TNF-α on primary human astrocytes. We found that QUIN induces IL-1β expression, a key mediator in AD pathogenesis, in human astrocytes. We also explored the effect of QUIN on astrocyte morphology and functions. At low concentrations, QUIN treatment induced concomitantly a marked increase in glial fibrillary acid protein levels and reduction in vimentin levels compared to controls; features consistent with astrogliosis. At pathophysiological concentrations QUIN induced a switch between structural protein expressions in a dose dependent manner, increasing VIM and concomitantly decreasing GFAP expression. Glutamine synthetase (GS) activity was used as a functional metabolic test for astrocytes. We found a significant dose-dependent reduction in GS activity following QUIN treatment. All together, this study showed that QUIN is an important factor for astroglial activation, dysregulation and cell death with potential relevance to AD and other neuroinflammatory diseases.
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Affiliation(s)
- Ka Ka Ting
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, Australia.
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Excitotoxic neonatal damage induced by monosodium glutamate reduces several GABAergic markers in the cerebral cortex and hippocampus in adulthood. Int J Dev Neurosci 2009; 27:845-55. [DOI: 10.1016/j.ijdevneu.2009.07.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Revised: 07/07/2009] [Accepted: 07/29/2009] [Indexed: 11/23/2022] Open
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Shang YC, Chong ZZ, Hou J, Maiese K. The forkhead transcription factor FOXO3a controls microglial inflammatory activation and eventual apoptotic injury through caspase 3. Curr Neurovasc Res 2009; 6:20-31. [PMID: 19355923 DOI: 10.2174/156720209787466064] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Memory loss and cognitive failure are increasingly being identified as potential risks with the recognized increase in life expectancy of the general population. As a result, the development of novel therapeutic strategies for disorders such as Alzheimer's disease have garnered increased attention. The etiologies that can lead to Alzheimer's disease are extremely varied, but a number of therapeutic options are directed against amyloid-beta peptide and inflammatory cell regulation to prevent or halt progressive cognitive loss. In particular, inflammatory microglial cells may have disparate functions that in some scenarios lead to disability through the removal of functional neurovascular cells and in other circumstances foster tissue repair. Given the significance microglial cells hold for neurodegenerative disorders, we therefore examined the function that amyloid (Abeta(1-42)) has upon the microglial cell line EOC 2 and identified a novel role for the forkhead transcription factor FoxO3a and caspase 3. Here we show that Abeta(1-42) leads to progressive injury and apoptotic cell loss in microglial cells that involves both early phosphatidylserine (PS) externalization and late genomic DNA fragmentation over a 24 hour course. Prior to these injury programs, Abeta(1-42) results in the activation and proliferation of microglia as demonstrated by increased proliferating cell nuclear antigen (PCNA) expression and bromodeoxyuridine (BrdU) uptake. Both apoptotic injury as well as the prior activation and proliferation of microglial cells relies upon the presence of FoxO3a, since specific gene silencing of FoxO3a promotes microglial cell protection and prevents the early activation and proliferation of these cells. Furthermore, Abeta(1-42) exposure maintained FoxO3a in an unphosphorylated "active" state and facilitated the cellular trafficking of FoxO3a from the cytoplasm to the cell nucleus to potentially lead to "pro-apoptotic" programs by this transcription factor. One apoptotic program in particular appears to involve the activation of caspase 3, since loss of FoxO3a through gene silencing prevents the induction of caspase 3 activity by Abeta(1-42).
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Affiliation(s)
- Yan Chen Shang
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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S100β Protein Expression: Gender- and Age-Related Daily Changes. Neurochem Res 2009; 34:1355-62. [DOI: 10.1007/s11064-009-9915-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/10/2009] [Indexed: 12/22/2022]
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Dietary tryptophan restriction in rats triggers astrocyte cytoskeletal hypertrophy in hippocampus and amygdala. Neurosci Lett 2009; 450:242-5. [DOI: 10.1016/j.neulet.2008.12.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Revised: 12/03/2008] [Accepted: 12/05/2008] [Indexed: 11/21/2022]
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Jang S, Suh SH, Yoo HS, Lee YM, Oh S. Changes in iNOS, GFAP and NR1 expression in various brain regions and elevation of sphingosine-1-phosphate in serum after immobilized stress. Neurochem Res 2007; 33:842-51. [PMID: 17940874 DOI: 10.1007/s11064-007-9523-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Accepted: 10/01/2007] [Indexed: 12/31/2022]
Abstract
Several studies have been suggested that long-term exposure to stress has detrimental effects on various brain functions and leads to neurodegenerative changes. However, the precise mechanism by which stress induces brain damage or neurodegenerative change is still a matter of debate. This study investigated the damage of neuronal cells involving in the expression of iNOS, NR1, and GFAP in various brain regions and characterized the change of sphingolipid metabolites as a biomarker of physiological change in serum after 3 weeks of repeated immobilization. In this report, the expression of iNOS, GFAP and NR1 in the brain of rats exposed to chronic immobilization stress was investigated. The expression of iNOS, GFAP and NR1 was elevated in the cortex and hippocampal area after 3 weeks of repeated immobilization. Immunoreactivity for GFAP and vimentin, as a marker of reactive gliosis, was also elevated in the cortex and hippocampus. The level of sphingolipids was measured in order to assess the changes in sphingolipid metabolites in the serum of rats exposed to stress. Interestingly, the level of So-1-P was increased in the plasma of rats subjected to 6-h immobilization stress than repeated immobilization. To further investigate the modulating effect of increased So-1-P in various brain regions, So-1-P was infused into the lateral cerebroventricle at a rate of 100 pmol/10 mul/h for 7 days. The expression of iNOS and NR1 was elevated in the cortex, hippocampus, striatum, and cerebellum after So-1-P infusion into the cerebroventricle, while the level of GFAP was elevated in the hippocampus and striatum. Interestingly, the expression levels of iNOS, GFAP, and NR1 were increased by the direct application of So-1-P to cultured cortical cells. These results suggest that NO production via iNOS expression, the NR1 expression, the activation of astrocytes, and the elevation of So-1-P may cause neurodegenerative changes in rats subjected to chronic immobilization and that the elevation of So-1-P by stress exposure would be one of the stress signal molecules.
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Affiliation(s)
- Soyong Jang
- Department of Neuroscience and Medical Research Institute, School of Medicine, Ewha Womans University, Mok-dong, Yangchon-ku, Seoul 158-710, Korea
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29
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Coecke S, Goldberg AM, Allen S, Buzanska L, Calamandrei G, Crofton K, Hareng L, Hartung T, Knaut H, Honegger P, Jacobs M, Lein P, Li A, Mundy W, Owen D, Schneider S, Silbergeld E, Reum T, Trnovec T, Monnet-Tschudi F, Bal-Price A. Workgroup report: incorporating in vitro alternative methods for developmental neurotoxicity into international hazard and risk assessment strategies. ENVIRONMENTAL HEALTH PERSPECTIVES 2007; 115:924-31. [PMID: 17589601 PMCID: PMC1892131 DOI: 10.1289/ehp.9427] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2006] [Accepted: 02/06/2007] [Indexed: 05/16/2023]
Abstract
This is the report of the first workshop on Incorporating In Vitro Alternative Methods for Developmental Neurotoxicity (DNT) Testing into International Hazard and Risk Assessment Strategies, held in Ispra, Italy, on 19-21 April 2005. The workshop was hosted by the European Centre for the Validation of Alternative Methods (ECVAM) and jointly organized by ECVAM, the European Chemical Industry Council, and the Johns Hopkins University Center for Alternatives to Animal Testing. The primary aim of the workshop was to identify and catalog potential methods that could be used to assess how data from in vitro alternative methods could help to predict and identify DNT hazards. Working groups focused on two different aspects: a) details on the science available in the field of DNT, including discussions on the models available to capture the critical DNT mechanisms and processes, and b) policy and strategy aspects to assess the integration of alternative methods in a regulatory framework. This report summarizes these discussions and details the recommendations and priorities for future work.
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Affiliation(s)
- Sandra Coecke
- ECVAM-European Centre for the Validation of Alternative Methods, Institute for Health and Consumer Protection, European Commission, Joint Research Center, Ispra, Italy.
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30
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Chong ZZ, Li F, Maiese K. Cellular demise and inflammatory microglial activation during beta-amyloid toxicity are governed by Wnt1 and canonical signaling pathways. Cell Signal 2007; 19:1150-62. [PMID: 17289346 PMCID: PMC1913492 DOI: 10.1016/j.cellsig.2006.12.009] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Revised: 12/06/2006] [Accepted: 12/14/2006] [Indexed: 11/24/2022]
Abstract
Initially described as a modulator of embryogenesis for a number of organ systems, Wnt1 has recently been linked to the development of several neurodegenerative disorders, none being of greater significance than Alzheimer's disease. We therefore examined the ability of Wnt1 to oversee vital pathways responsible for cell survival during beta-amyloid (Abeta1-42) exposure. Here we show that Wnt1 is critical for protection in the SH-SY5Y neuronal cell line against genomic DNA degradation, membrane phosphatidylserine (PS) exposure, and microglial activation, since these neuroprotective attributes of Wnt1 are lost during gene silencing of Wnt1 protein expression. Intimately tied to Wnt1 protection is the presence and activation of Akt1. Pharmacological inhibition of the PI 3-K pathway or gene silencing of Akt1 expression can abrogate the protective capacity of Wnt1. Closely aligned with Wnt1 and Akt1 are the integrated canonical pathways of synthase kinase-3beta (GSK-3beta) and beta-catenin. Through Akt1 dependent pathways, Wnt1 phosphorylates GSK-3beta and maintains beta-catenin integrity to insure its translocation from the cytoplasm to the nucleus to block apoptosis. Our work outlines a highly novel role for Wnt1 and its integration with Akt1, GSK-3beta, and beta-catenin to foster neuronal cell survival and repress inflammatory microglial activation that can identify new avenues of therapy against neurodegenerative disorders.
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Affiliation(s)
- Zhao Zhong Chong
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Faqi Li
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Kenneth Maiese
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201
- Departments of Neurology and Anatomy & Cell Biology, Center for Molecular Medicine and Genetics, Institute of Environmental Health Sciences, Wayne State University School of Medicine, Detroit, Michigan 48201
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31
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Jang S, Lee JH, Choi KR, Kim D, Yoo HS, Oh S. Cytochemical alterations in the rat retina by LPS administration. Neurochem Res 2006; 32:1-10. [PMID: 17160463 DOI: 10.1007/s11064-006-9215-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2006] [Accepted: 10/30/2006] [Indexed: 01/04/2023]
Abstract
LPS-induced inflammation and changes in protein phosphorylation and the JAK-STAT pathway accompanying glial activation after LPS treatment, were followed by analyzing secreted proinflammatory cytokine levels. The administration of LPS caused tyrosine phosphorylation of STAT3 in retinae and induced glial fibrillary acidic protein. (GFAP) from the nerve fiber layer to the ganglion cell layer. Our results suggest that the LPS-induced activation of the JAK2/STAT3 signaling pathway may play a key role in the induction of astrogliosis. However, no significant increase in vimentin, OX-42 or inducible nitric oxide synthase (iNOS) expressions were observed after LPS administration. Sphingosine kinase catalyzes the conversion of sphingosine to sphingosine-1-phosphate (So-1-P), a sphingolipid metabolite that plays important roles in angiogenesis, inflammation, and cell growth. In the present study, it was found that sphingolipid metabolite levels were elevated in the serum and retinae of LPS-injected rats. To further investigate the chronic effect of increased So-1-P in the retina, So-1-P was infused intracerebroventricularly (i.c.v.) into rats using an osmotic minipump at 100 pmol/10 microl h(-1) for 7 days, and was found to increase retinal GFAP expression. These observations suggest that LPS induces the activation of retinal astrocytes via JAK2/STAT3 and that LPS affects So-1-P generation. Our findings also suggest that elevated So-1-P in the retina and/or in serum could induce cytochemical alterations in LPS treated or inflamed retinae.
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Affiliation(s)
- Soyong Jang
- Department of Neuroscience and Medical Research Institute, College of Medicine, Ewha Womans University, Seoul 158-710, Korea
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32
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Beas-Zárate C, Ureña-Guerrero ME, Flores-Soto M, Armendariz-Borunda J, Ortuño-Sahagún D. The expression and binding of kainate receptors is modified in different brain regions by glutamate neurotoxicity during postnatal rat development. Int J Dev Neurosci 2006; 25:53-61. [PMID: 17141463 DOI: 10.1016/j.ijdevneu.2006.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2006] [Revised: 10/20/2006] [Accepted: 10/23/2006] [Indexed: 10/23/2022] Open
Abstract
Kainic acid receptor (KA-R) subunits are differentially expressed during brain development, and they modulate both neural growth and survival. High concentrations of glutamate in the brain can induce neuronal injury through these receptors, altering normal development. However, it is unclear whether KAR subunit expression itself is also modified by neonatal exposure to high glutamate. To analyze this, monosodium glutamate (4mg/g of body weight) was subcutaneously administered on postnatal days 1, 3, 5 and 7, and the expression of GluR5, GluR6, KA1 and KA2, as well as [(3)H]-kainic acid (KA-R) binding, was evaluated on postnatal days 14, 21, 30 and 60 in different regions of rat brain. As a result, high levels of GluR5 expression associated with strong [(3)H]-kainic acid binding were observed on postnatal days 30 and 60 in the cerebral cortex of rats exposed to glutamate. Similarly, the changes induced by glutamate administration in the expression of the KA1 and KA2 subunits were paralleled by those of [(3)H]-kainic acid binding in the striatum at postnatal days 21 and 30. In contrast, while KAR subunits were over expressed in the hippocampus, no changes were observed in [(3)H]-kainic acid binding in adult rats that had been exposed to glutamate. Therefore, glutamate modifies both the expression of kainic acid receptor subunits and kainic acid binding in a determined spatial and temporal manner, which may be indicative of a regional susceptibility to glutamate neurotoxicity.
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Affiliation(s)
- C Beas-Zárate
- Laboratorio de Neurobiología Celular y Molecular, División de Neurociencias, CIBO, IMSS, Mexico.
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33
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Kreutz S, Koch M, Ghadban C, Korf HW, Dehghani F. Cannabinoids and neuronal damage: differential effects of THC, AEA and 2-AG on activated microglial cells and degenerating neurons in excitotoxically lesioned rat organotypic hippocampal slice cultures. Exp Neurol 2006; 203:246-57. [PMID: 17010339 DOI: 10.1016/j.expneurol.2006.08.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 08/07/2006] [Accepted: 08/10/2006] [Indexed: 11/25/2022]
Abstract
Cannabinoids (CBs) are attributed neuroprotective effects in vivo. Here, we determined the neuroprotective potential of CBs during neuronal damage in excitotoxically lesioned organotypic hippocampal slice cultures (OHSCs). OHSCs are the best characterized in vitro model to investigate the function of microglial cells in neuronal damage since blood-borne monocytes and T-lymphocytes are absent and microglial cells represent the only immunocompetent cell type. Excitotoxic neuronal damage was induced by NMDA (50 microM) application for 4 h. Neuroprotective properties of 9-carboxy-11-nor-delta-9-tetrahydrocannabinol (THC), N-arachidonoylethanolamide (AEA) or 2-arachidonoylglycerol (2-AG) in different concentrations were determined after co-application with NMDA by counting degenerating neurons identified by propidium iodide labeling (PI(+)) and microglial cells labeled by isolectin B(4) (IB(4)(+)). All three CBs used significantly decreased the number of IB(4)(+) microglial cells in the dentate gyrus but the number of PI(+) neurons was reduced only after 2-AG treatment. Application of AM630, antagonizing CB2 receptors highly expressed by activated microglial cells, did not counteract neuroprotective effects of 2-AG, but affected THC-mediated reduction of IB(4)(+) microglial cells. Our results indicate that (1) only 2-AG exerts neuroprotective effects in OHSCs; (2) reduction of IB(4)(+) microglial cells is not a neuroprotective event per se and involves other CB receptors than the CB2 receptor; (3) the discrepancy in the neuroprotective effects of CBs observed in vivo and in our in vitro model system may underline the functional relevance of invading monocytes and T-lymphocytes that are absent in OHSCs.
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MESH Headings
- Animals
- Animals, Newborn
- Arachidonic Acids/pharmacology
- Arachidonic Acids/therapeutic use
- Brain/drug effects
- Brain/pathology
- Brain/physiopathology
- Brain Damage, Chronic/drug therapy
- Brain Damage, Chronic/metabolism
- Brain Damage, Chronic/physiopathology
- Cannabinoids/pharmacology
- Cannabinoids/therapeutic use
- Cell Count
- Disease Models, Animal
- Dronabinol/pharmacology
- Dronabinol/therapeutic use
- Endocannabinoids
- Gliosis/drug therapy
- Gliosis/metabolism
- Gliosis/physiopathology
- Glycerides/pharmacology
- Glycerides/therapeutic use
- Microglia/drug effects
- Microglia/metabolism
- N-Methylaspartate/antagonists & inhibitors
- N-Methylaspartate/toxicity
- Nerve Degeneration/drug therapy
- Nerve Degeneration/metabolism
- Nerve Degeneration/physiopathology
- Neurons/drug effects
- Neurons/metabolism
- Neurons/pathology
- Neuroprotective Agents/pharmacology
- Neuroprotective Agents/therapeutic use
- Neurotoxins/antagonists & inhibitors
- Neurotoxins/toxicity
- Organ Culture Techniques
- Plant Lectins
- Polyunsaturated Alkamides/pharmacology
- Polyunsaturated Alkamides/therapeutic use
- Rats
- Rats, Wistar
- Receptor, Cannabinoid, CB2/antagonists & inhibitors
- Receptor, Cannabinoid, CB2/metabolism
- Treatment Outcome
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Affiliation(s)
- Susanne Kreutz
- Dr. Senckenbergische Anatomie, Institut für Anatomie 2, Johann Wolfgang Goethe-Universität Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany
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Segura Torres JE, Chaparro-Huerta V, Rivera Cervantres MC, Montes-González R, Flores Soto ME, Beas-Zárate C. Neuronal cell death due to glutamate excitotocity is mediated by P38 activation in the rat cerebral cortex. Neurosci Lett 2006; 403:233-8. [PMID: 16782274 DOI: 10.1016/j.neulet.2006.04.063] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2006] [Revised: 04/04/2006] [Accepted: 04/20/2006] [Indexed: 01/03/2023]
Abstract
Excitotoxic neuronal death occurs through the activation of NMDA and non-NMDA glutamatergic receptors in the CNS. Glutamate also induces strong activation of p38 and indeed, cell death can be prevented by inhibitors of the p38 pathway. Furthermore, intracellular signals generated by AMPA receptors activate the stress sensitive MAP kinases implicated in apoptotic neuronal death, such as JNK and p38. To investigate the relationship between these elements, we have used immunohistochemistry to analyze the expression of GluR2 in the cerebral cortex of postnatal rats (postnatal Day [PD] 8 and 14) after administering them with monosodium glutamate (MSG; 4 mg/g body weight on PD1, 3, 5, and 7). Similarly, the expression of REST, Fas-L and Bcl-2 mRNA transcripts in animals exposed to a p38 inhibitor, SB203580 (0.42 microg/g body weight, administered subcutaneously) was determined by reverse transcriptase-PCR. The enhanced GluR2-expression in the cerebral cortex at PD8 and the down regulation of this receptor at PD14 was correlated with neuronal damage induced by excitotoxicity. In addition, the enhanced expression of REST at PD8 and PD14 suggests that the induction of REST transcription contributes to glutamate-induced excitotoxic neurodegeneration, possibly by modulating GluR2 expression. Fas-L and Bcl-2 over expression at PD8 and their subsequent down regulation at PD14 also suggests that Fas-L could be the direct effector of apoptosis in the cerebral cortex. On the other hand, the presence of Bcl-2 at PD8 could attenuate certain survival signals in neurons under these neurotoxic conditions. Thus, a change in glutamate receptor composition, and enhanced Fas-L and Bcl-2 expression, coupled with activation of the p38/SAPK pathway appear to be events involved in the neuronal apoptosis induced under neurotoxic conditions.
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Affiliation(s)
- J E Segura Torres
- Laboratorio de Neurobiología Celular and Molecular, División de Neurociencias, CIBO, Instituto Mexicano del Seguro Social, Apdo. Postal #4-160, Guadalajara, Jalisco 44421, Mexico
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35
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Gordo AC, Falcão AS, Fernandes A, Brito MA, Silva RFM, Brites D. Unconjugated bilirubin activates and damages microglia. J Neurosci Res 2006; 84:194-201. [PMID: 16612833 DOI: 10.1002/jnr.20857] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Microglia are the resident immune cells of the brain and are the principal source of cytokines produced during central nervous system inflammation. We have previously shown that increased levels of unconjugated bilirubin (UCB), which can be detrimental to the central nervous system during neonatal life, induce the secretion of inflammatory cytokines and glutamate by astrocytes. Nevertheless, the effect of UCB on microglia has never been investigated. Hence, the main goal of the present study was to evaluate whether UCB leads to microglial activation and to the release of the cytokines tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-6. Additionally, we investigated the effects of UCB on glutamate efflux and cell death. The results showed that UCB induces morphological changes characteristic of activated microglia and the release of high levels of TNF-alpha, IL-1beta, and IL-6 in a concentration-dependent manner. In addition, UCB triggered extracellular accumulation of glutamate and an increased cell death by apoptosis and necrosis. These results demonstrate, for the first time, that UCB is toxic to microglial cells and point to microglia as an important target of UCB in the central nervous system. Moreover, they suggest that UCB-induced cytokine production, by mediating cell injury, can further contribute to exacerbate neurototoxicity. Interestingly, microglia cells are much more responsive to UCB than astrocytes. Collectively, these data indicate that microglia may play an important role in the pathogenesis of encephalopathy during severe hyperbilirubinemia.
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Affiliation(s)
- Ana C Gordo
- Centro de Patogénese Molecular-UBMBE, Faculdade de Farmácia, University of Lisbon, Lisbon, Portugal
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36
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Chong ZZ, Kang J, Li F, Maiese K. mGluRI targets microglial activation and selectively prevents neuronal cell engulfment through Akt and caspase dependent pathways. Curr Neurovasc Res 2005; 2:197-211. [PMID: 16181114 PMCID: PMC1986675 DOI: 10.2174/1567202054368317] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Metabotropic glutamate receptors (mGluRs) are expressed throughout the mammalian central nervous system and integrate a host of signal transduction pathways that determine cellular function, plasticity and injury. Yet, one of the more unique regulatory functions of this family of GTP-binding proteins involves cytoprotection in the nervous system. Here, we demonstrate that activation of group I metabotropic glutamate receptors (mGluRIs) in primary hippocampal neurons not only provides intrinsic cellular protection for the maintenance of genomic DNA integrity, but also prevents inflammatory microglial activation and specific neuronal cell engulfment during free radical oxidative stress. Loss of cellular membrane asymmetry and exposure of membrane phosphatidylserine (PS) residues were necessary and sufficient to result in microglial activation and proliferation, since administration of an antibody to the PS receptor could block microglial activity. Through the continuous assessment of individual neurons in real time, activation of mGluRIs was documented to block neuronal PS exposure and prevented subsequent neuronal cell engulfment by microglia seeking "PS tagged" neurons. Furthermore, regulation of both cellular integrity and microglial activity by mGluRI activation was dependent upon the activation and phosphorylation of protein kinase B (Akt1), prevention of mitochondrial membrane depolarization with associated permeability transition pore complex formation, and the down regulation of caspase 9-like activity. Our work defines a significant role of mGluRIs for the modulation of cellular survival and inflammation in the nervous system during oxidative stress.
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Affiliation(s)
- Zhao Zhong Chong
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, 4201 St. Antoine, Detroit, Michigan 48201, USA
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37
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Falcão AS, Fernandes A, Brito MA, Silva RFM, Brites D. Bilirubin-induced inflammatory response, glutamate release, and cell death in rat cortical astrocytes are enhanced in younger cells. Neurobiol Dis 2005; 20:199-206. [PMID: 16242628 DOI: 10.1016/j.nbd.2005.03.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2005] [Revised: 02/25/2005] [Accepted: 03/03/2005] [Indexed: 11/21/2022] Open
Abstract
Unconjugated bilirubin (UCB) encephalopathy is a predominantly early life condition resulting from the impairment of several cellular functions in the brain of severely jaundiced infants. However, only few data exist on the age-dependent effects of UCB and their association with increased vulnerability of premature newborns, particularly in a sepsis condition. We investigated cell death, glutamate efflux, and inflammatory cytokine dynamics after exposure of astrocytes at different stages of differentiation to clinically relevant concentrations of UCB and/or lipopolysaccharide (LPS). Younger astrocytes were more prone to UCB-induced cell death, glutamate efflux, and inflammatory response than older ones. Furthermore, in immature cells, LPS exacerbated UCB effects, such as cell death by necrosis. These findings provide a basis for the increased susceptibility of premature newborns to UCB deleterious effects, namely when associated with sepsis, and underline how crucial the course of cell maturation can be to UCB encephalopathy during moderate to severe neonatal jaundice.
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Affiliation(s)
- Ana S Falcão
- Centro de Patogénese Molecular (UBMBE), Faculdade de Farmácia, University of Lisbon, Av. Forças Armadas, 1600-083 Lisboa, Portugal
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38
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Chaparro-Huerta V, Rivera-Cervantes MC, Flores-Soto ME, Gómez-Pinedo U, Beas-Zárate C. Proinflammatory cytokines and apoptosis following glutamate-induced excitotoxicity mediated by p38 MAPK in the hippocampus of neonatal rats. J Neuroimmunol 2005; 165:53-62. [PMID: 15972237 DOI: 10.1016/j.jneuroim.2005.04.025] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2004] [Revised: 04/08/2005] [Accepted: 04/08/2005] [Indexed: 11/24/2022]
Abstract
The proinflammatory cytokines TNF-alpha, IL-1beta, and IL-6 rise during neuronal damage and activate the apoptotic mitogen-activated protein kinase p38. We studied apoptosis, the levels of TNF-alpha, IL-1beta, and IL-6, and the cell type producing TNF-alpha in rats at 8, 10, and 14 days of age after neonatal exposure to glutamate, which induces neuronal damage. TNF-alpha production was significantly increased by glutamate, but inhibited by SB203580 (a p38 inhibitor). TNF-alpha, IL-1beta, and IL-6 mRNA levels increased, but SB203580 did not modify their expression. Thus, the p38 signaling pathway influences the expression of inflammatory genes and its inhibition may offer anti-inflammatory therapy.
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Affiliation(s)
- V Chaparro-Huerta
- Laboratorio de Neurobiología Molecular, División de Neurociencias, Centro de Investigación Biomédica de Occidente (CIBO), Instituto Mexicano del Seguro Social (IMSS), Guadalajara, México
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39
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López-Pérez SJ, Vergara P, Ventura-Valenzuela JP, Ureña-Guerrero ME, Segovia J, Beas-Zárate C. Modification of dopaminergic markers expression in the striatum by neonatal exposure to glutamate during development. Int J Dev Neurosci 2005; 23:335-42. [PMID: 15927757 DOI: 10.1016/j.ijdevneu.2004.12.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2004] [Revised: 12/14/2004] [Accepted: 12/15/2004] [Indexed: 11/21/2022] Open
Abstract
Monosodium l-glutamate (MSG) was administered subcutaneously to male neonatal rats, and the effect on developmental profile of tyrosine hydroxylase (TH), D1, D2 receptors, and dopamine (DA) transporter expression in the striatum was examined using Western blot. In addition, TH-immunopositive neurons at substantia nigra (SN) were also examined. MSG treatment (4mg/g of body weight, administered on postnatal days 1, 3, 5, and 7) resulted in a reduction of D1 and D2 receptor expression from 30 days of age and persisted to adulthood (120 days of age), while DA transporter expression was significantly reduced from 14 days of age to adulthood. TH immunopositive neurons at SN showed a significant reduction, as well as TH expression on postnatal days 10, 30, 60, and 120 at striatum was reduced. No changes of TH were observed at 14 days of age. Results indicate that an over-stimulation of the glutamatergic system by neonatal exposure to a high glutamate concentration induces a partial loss in TH-positive neurons in the SN and an important reduction in dopaminergic markers expression in the striatum, suggesting that early excitotoxicity could contribute to developmental alterations in the nigrostriatal pathway, which may be associated with various disorders of the basal ganglia.
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Affiliation(s)
- S J López-Pérez
- Lab. de Neurobiología., Depto. de Biol. Cel. y Mol., C.U.C.B.A., U. de G., Guadalajara, Jalisco, Mexico
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40
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Chang MS, Ariah LM, Marks A, Azmitia EC. Chronic gliosis induced by loss of S-100B: knockout mice have enhanced GFAP-immunoreactivity but blunted response to a serotonin challenge. Brain Res 2005; 1031:1-9. [PMID: 15621007 DOI: 10.1016/j.brainres.2004.07.043] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2004] [Indexed: 10/26/2022]
Abstract
Serotonin (5-HT) can induce a release of intraglial S-100B and produce a change in glial morphology. Because S-100B can inhibit polymerization of glial fibrillary acidic protein (GFAP), we hypothesize that glial reactivity may reflect the loss of intraglial S-100B. Adult male transgenic S-100B homozygous knockout (-/-) mice (KO) and wild-type CD-1 (WT) mice were studied. S-100B-immunoreactivity (IR) was seen in the brain tissue of WT (CD-1) but not S-100B KO (-/-) mice. GFAP-IR was seen in both WT (CD-1) and S-100B KO (-/-) glia cells, but S-100B KO (-/-) GFAP-IR cells appeared larger, darker, and more branched than in WT (CD-1). To compare the response of GFAP-IR cells to 5-HT in S-100B KO (-/-) and WT (CD-1) mice, we injected animals with para-chloroamphetamine (PCA) over 2 days (5 and 10 mg/ml). PCA is a potent 5-HT releaser which can induce gliosis in the rodent brain. In WT (CD-1) mice, the size, branching, and density of GFAP-IR cells were significantly increased after PCA injections. No increase in GFAP-IR activation was seen in the S-100B KO (-/-) after PCA injections. Cell-specific densitometry (set at a threshold of 0-150 based on a scale of 255) in these animals statistically showed an increase in GFAP-IR after PCA injections in WT (CD-1) but not S-100B KO (-/-) mice. These results are consistent with the hypothesis that 5-HT may modulate glial morphology by inducing a release of intracellular S-100B, and this pathway is inoperable in the S-100B KO (-/-).
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Affiliation(s)
- Matthew S Chang
- Department of Biology, New York University, 10-09 Silver Building; 100 Washington Square East, New York, NY 10003 USA
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Campisi A, Caccamo D, Li Volti G, Currò M, Parisi G, Avola R, Vanella A, Ientile R. Glutamate-evoked redox state alterations are involved in tissue transglutaminase upregulation in primary astrocyte cultures. FEBS Lett 2004; 578:80-4. [PMID: 15581620 DOI: 10.1016/j.febslet.2004.10.074] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2004] [Revised: 10/04/2004] [Accepted: 10/29/2004] [Indexed: 11/17/2022]
Abstract
The aim of this study was to evaluate the involvement of oxidative stress in glutamate-evoked transglutaminase (TGase) upregulation in astrocyte cultures (14 DIV). A 24 h exposure to glutamate caused a dose-dependent depletion of glutathione intracellular content and increased the ROS production in cell cultures. These effects were receptor-mediated, as demonstrated by inhibition with GYKI 52466. The pre-incubation with glutathione ethyl ester or cysteamine recovered oxidative status and was effective in significantly reducing glutamate-increased tissue TGase. These data suggest that tissue TGase upregulation may be part of a biochemical response to oxidative stress induced by a prolonged exposure of astrocyte cultures to glutamate.
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Affiliation(s)
- A Campisi
- Department of Biological Chemistry, Medical Chemistry and Molecular Biology, University of Catania, V.le A. Doria, 6, 95100 Catania, Italy
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Fernandes A, Silva RFM, Falcão AS, Brito MA, Brites D. Cytokine production, glutamate release and cell death in rat cultured astrocytes treated with unconjugated bilirubin and LPS. J Neuroimmunol 2004; 153:64-75. [PMID: 15265664 DOI: 10.1016/j.jneuroim.2004.04.007] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2004] [Revised: 04/21/2004] [Accepted: 04/21/2004] [Indexed: 11/19/2022]
Abstract
In hyperbilirubinemic newborns, sepsis is considered a risk factor for kernicterus. Evidence shows that injury to astrocytes triggers cytokine release. We examined the effects of unconjugated bilirubin (UCB) alone, or in combination with LPS, on the release of glutamate and cytokines from astrocytes in conditions inducing less than 10% of cell death. UCB leads to an increase of extracellular glutamate and highly enhances the release of TNF-alpha and IL-1beta, while inhibiting the production of IL-6. LPS potentiates immunostimulatory properties of UCB. These results point out the role of cytokines and provide a basis for the significance of sepsis in UCB encephalopathy.
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Affiliation(s)
- Adelaide Fernandes
- Centro de Patogénese Molecular (UBMBE), Faculdade de Farmácia, University of Lisbon, Av. Forças Armadas, 1600-083 Lisbon, Portugal
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Kang JQ, Chong ZZ, Maiese K. Akt1 protects against inflammatory microglial activation through maintenance of membrane asymmetry and modulation of cysteine protease activity. J Neurosci Res 2003; 74:37-51. [PMID: 13130504 DOI: 10.1002/jnr.10740] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In several cell systems, protein kinase B (Akt1) can promote cell growth and development, but the "antiapoptotic" pathways of this kinase that may offer protection against cellular inflammatory demise have not been defined. Given that early cellular membrane phosphatidylserine exposure is a critical component of apoptosis, we investigated the role of Akt1 during neuronal apoptotic injury. By employing differentiated SH-SY5Y neuronal cells that overexpress a constitutively active form of Akt1 (myristoylated Akt1), free radical-induced cell injury was assessed through trypan blue dye exclusion, DNA fragmentation, membrane phosphatidylserine exposure, protein kinase B phosphorylation, cysteine protease activity, and mitochondrial membrane potential. Membrane phosphatidylserine exposure was both necessary and sufficient for microglial activation, insofar as cotreatment with an antiphosphatidylserine receptor-neutralizing antibody could prevent microglial activity following neuronal loss of membrane asymmetry. Furthermore, expression of myristoylated Akt1 not only prevented cell injury through the prevention of membrane phosphatidylserine exposure and genomic DNA fragmentation but also inhibited microglial activation and proliferation that required the inhibition of caspase 9-, caspase 3-, and caspase 1-like activities linked to cytochrome c release. Interestingly, Akt1 modulation of membrane phosphatidylserine exposure was primarily through caspase 1 activity. Removal of Akt1 activity abolished neuronal protection, suggesting that Akt1 functions as a critical pathway for the maintenance of cellular integrity and the prevention of phagocytic cellular removal during neurodegenerative insults.
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Affiliation(s)
- Jing-Qiong Kang
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Kang JQ, Chong ZZ, Maiese K. Critical role for Akt1 in the modulation of apoptotic phosphatidylserine exposure and microglial activation. Mol Pharmacol 2003; 64:557-69. [PMID: 12920191 DOI: 10.1124/mol.64.3.557] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Biological targets for neurodegenerative disease that focus on the intrinsic maintenance of cellular integrity and the extrinsic prevention of phagocytic cellular disposal offer the greatest promise for therapeutic intervention. Protein kinase B (Akt1), a serine-threonine kinase closely involved in cell growth and survival, offers a strong potential to address both intrinsic and extrinsic mechanisms of neuronal injury. We demonstrate that overexpression of a constitutively active form of Akt1 (myristoylated Akt1) in differentiated SH-SY5Y neuronal cells provides intrinsic cellular protection against apoptotic genomic DNA destruction and membrane phosphatidylserine (PS) exposure. Transfection of SH-SY5Y cells with a plasmid encoding a kinase-deficient dominant-negative Akt1 eliminates cytoprotection, suggesting that activation of Akt1 is necessary and sufficient to prevent apoptotic destruction. Apoptotic neuronal membrane PS exposure provides a unique pathway for Akt1 to offer extrinsic cellular protection and block microglial activation, because independent cotreatment with an anti-PS receptor neutralizing antibody could also prevent microglial proliferation. Akt1 maintains nuclear DNA integrity and membrane PS exposure through the specific inhibition of caspase 3-, 8-, and 9-like activities that were linked to mitochondrial membrane potential and cytochrome c release. Our work elucidates a novel capacity for Akt1 to maintain cellular integrity through a series of cysteine protease pathways and to uniquely regulate microglial activation through the modulation of membrane PS residue externalization.
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Affiliation(s)
- Jing-Qiong Kang
- Department of Neurology, 8C-1 UHC, Wayne State University School of Medicine, 4201 St. Antoine, Detroit, MI 48201, USA
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Chaparro-Huerta V, Rivera-Cervantes MC, Torres-Mendoza BM, Beas-Zárate C. Neuronal death and tumor necrosis factor-alpha response to glutamate-induced excitotoxicity in the cerebral cortex of neonatal rats. Neurosci Lett 2002; 333:95-8. [PMID: 12419489 DOI: 10.1016/s0304-3940(02)01006-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Neuronal death and lactate dehydrogenase (LDH) activity were evaluated in the cerebral cortices of neonatal rats after exposure to monosodium L-glutamate (MSG) to induce neuroexcitotoxicity. A time-response profile for tumor necrosis factor-alpha (TNF-alpha) expression was drawn, with measurements taken every 6 h after the first dose of MSG during the first 8 postnatal days, and at days 10 and 14 after birth. An increase in neuronal loss accompanied by high LDH activity and high TNF-alpha levels was observed at 8 and 10 days. These results indicate that neuronal loss may occur via an apoptosis-like mechanism directed selectively against neurons that express glutamate receptors, mainly the N-methyl-D-aspartate, which it may be strengthen by high TNF-alpha levels through a feedback mechanism to induce cell death via apoptosis.
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Affiliation(s)
- V Chaparro-Huerta
- División de Neurociencias, Centro de Investigación Biomédica de Occidente (CIBO), Instituto Mexicano del Seguro Social (IMSS), P.O. 4-160, Guadalajara, Jalisco 44421, Mexico
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